Water Stone

The Water Stone, first appearing in Pokémon Red, Blue, and Yellow games and appearing in every game ever since, is a one-time-use item that can be used to evolve certain water-type Pokémon. It is the only way these certain Pokémon can evolve. The water stone also unlocks a chamber in the Ruins of Alph in Pokémon HeartGold and SoulSilver, or when it is in the bag in Pokémon Crystal.

• This item can be bought in certain shops in-game on some generations and game cartridges.

• This item can be traded between Red, Blue, Yellow, Gold, Silver, Crystal, Ruby, Sapphire, Emerald, FireRed, LeafGreen, Diamond, Pearl, Platinum, HeartGold, SoulSilver, Black, and White games, provided the Pokémon being traded is holding the Water Stone as its item and both game cartridges can trade back and forth.